linux-chatroom.rar_linux 多路复用

//--------------------------------server.c-------------------------------------------------- //包含工程所需的头文件 #include<stdio.h> #include<stdlib.h> #include<sys/types.h> //数据类型定义 #include<sys/stat.h> #include<netinet/in.h> //定义数据结构sockaddr_in #include<sys/socket.h> //提供socket函数及数据结构 #include<string.h> #include<unistd.h> #include<signal.h> #include<sys/ipc.h> #include<sys/shm.h> #include<errno.h> #include <arpa/inet.h> #define MYPORT 3490 //宏定义定义通信端口 #define BACKLOG 10 //宏定义，定义服务程序可以连接的最大客户数量 #define WELCOME "|----------Welcome to the chat room! ----------|" //宏定义，当客户端连接服务端时，想客户发送此欢迎字符串 //创建共享存储区 key_t shm_create(void) { key_t shmid; if((shmid = shmget(IPC_PRIVATE,1024,S_IRUSR|S_IWUSR)) == -1) { fprintf(stderr,"Create Share Memory Error:%s\n\a",strerror(errno)); exit(1); } return shmid; } //端口绑定函数,创建套接字，并绑定到指定端口 int bindPort(unsigned short int port) { int sockfd; struct sockaddr_in my_addr; sockfd = socket(AF_INET,SOCK_STREAM,0);//创建基于流套接字 my_addr.sin_family = AF_INET;//IPv4协议族 my_addr.sin_port = htons(port);//端口转换 my_addr.sin_addr.s_addr = INADDR_ANY; bzero(&(my_addr.sin_zero),0); if(bind(sockfd,(struct sockaddr *)&my_addr,sizeof(struct sockaddr)) == -1) { printf("bind error\n"); exit(1); } printf("bind success!\n"); return sockfd; } int main(int argc, char *argv[]) { int sockfd,clientfd,sin_size,recvbytes; //定义监听套接字、客户套接字 pid_t pid,ppid; //定义父子线程标记变量 char *buf, *r_addr, *w_addr, *temp;//="\0"; //定义临时存储区 struct sockaddr_in their_addr; //定义地址结构 key_t shmid; memset(&their_addr,0,sizeof(struct sockaddr_in)); shmid = shm_create(); //创建共享存储区 temp = (char *)malloc(255); sockfd = bindPort(MYPORT);//绑定端口 while(1) { if(listen(sockfd,BACKLOG) == -1)//在指定端口上监听 { printf("listen error\n"); exit(1); } printf("listening......\n"); clientfd = accept(sockfd,(struct sockaddr*)&their_addr,&sin_size) ; if(clientfd == -1)//接收客户端连接 { printf("accept error\n"); exit(1); } printf("accept from:%s\n",inet_ntoa(their_addr.sin_addr)); send(clientfd,WELCOME,strlen(WELCOME),0);//发送问候信息 buf = (char *)malloc(255); ppid = fork();//创建子进程 if(ppid == 0)//为子进程 { pid = fork(); //创建子进程 //while(1) //{ if(pid > 0) { while(1){//父进程用于接收信息 memset(buf,0,255); if((recvbytes = recv(clientfd,buf,255,0)) <= 0) { perror("recv1"); close(clientfd); raise(SIGKILL); exit(1); } w_addr = shmat(shmid, 0, 0); memset(w_addr, '\0', 1024); strncpy(w_addr, buf, 1024); printf(" %s\n",buf); } } else if(pid == 0) { while(1){//子进程用于发送信息 sleep(1); r_addr = shmat(shmid, 0, 0); if(strcmp(temp,r_addr) != 0) { strcpy(temp,r_addr); if(send(clientfd,r_addr,strlen(r_addr),0) == -1) { printf("send error\n"); } memset(r_addr, '\0', 1024); strcpy(r_addr,temp); } } } else perror("fork"); //} } } printf("------------------------------\n"); free(buf); close(sockfd); close(clientfd); return 0; }